Effect of TLR7 gene expression mediating NF-κB signaling pathway on the pathogenesis of bronchial asthma in mice and the intervention role of IFN-γ.

OBJECTIVE: To explore the mechanism of TLR7 mediating NF-κB signaling pathway on the pathogenesis of bronchial asthma in mice and the intervention effect of IFN-γ in the process. MATERIALS AND METHODS: The experimental animals were 70 C57BL/6J female mice of clean grade, which were divided into 7 groups according to different treatment protocols, including Normal group, Asthma group, Model+1-MT group, Model+IFN-γ group, Model+TLR7 agonist group, TLR7 deficient group, and Model+TLR7 deficient group. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of lung tissues. The positive expression rates of TLR7, p-IKKα and NF-κBp65 were detected by immunohistochemistry. bronchoalveolar lavage fluid (BALF) cells were classified and counted. The contents of interleukin (IL)-4, IL-10, IL-12 and interferon (IFN)-γ in BALF supernatant were detected by enzyme-linked immunosorbent assay (ELISA). Following isolation, culture and plasmid construction of airway smooth muscle cells (ASMCS) from normal mice and asthmatic mice, cells were transfected and divided into the Control group, pcDNA-TLR7 NC group, siRNA-TLR7 NC group, pcDNA-TLR7 group, siRNA-TLR7 group, Asatone group, Triptolide group, and pcDNA-TLR7 +Asatone group. The expression of TLR7, IDO, p-IKKα and NF-κBp65 was detected by real-time polymerase chain reaction (RT-PCR) and Western blot, respectively. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) was used to detect the proliferation of ASMCS. The cell cycle and apoptosis of ASMCS were detected by flow cytometry. RESULTS: HE staining showed successful modeling of asthma. Immunohistochemical test showed that the positive expression rate of TLR7 in the Asthma group was significantly decreased, and that of IKKα and NF-κBp65 was significantly increased, with significantly increased IL-4, IL-10, IL-12 and IFN-γ levels (all p<0.05). Model+1-MT group and Model+TLR7 deficient group had a large number of inflammatory cell infiltration, increased IL-4, IL-10, IL-12 and IFN-γ levels, decreased expression levels of TLR7 and IDO, and increased expression of p-IKKα and NF-κBp65 (all p<0.05); while the opposites results were detected in Model+IFN-γ group and Model+TLR7 agonist group (all p<0.05). Cell transfection experiments revealed that pcDNA-TLR7 group and Triptolide group had increased TLR7 expression while decreased p-IKKα and NF-κBp65, decreased proliferation level, and increased cell apoptosis (all p<0.05); while the contrary results were found in siRNA-TLR7 group and Asatone group (all p<0.05); yet without significant difference in pcDNA-TLR7+Asatone group (all p>0.05). CONCLUSIONS: Upregulation of TLR7 can inhibit the activation of NF-κB signaling pathway, reduces airway inflammation, inhibits ASMCS proliferation and thus promotes cell apoptosis in asthmatic mice. Besides, IFN-γ can exert a protective role in suppressing the progression of inflammation in asthma.

[Rapid location of nasointestinal tube by bedside ultrasound for critical patients in emergency intensive care unit].

OBJECTIVE: To evaluate the feasibility of method of bedside ultrasound to confirm correct nasointestinal tube placement of critical patients. METHODS: From June 2015 to February 2016 , a total of 70 patients admitted to Emergency Intensive Care Unit, Zhejiang Provincial People's Hospital, 37 males and 33 females, using bedside ultrasound(vessels signe) to confirm the location of nasointestinal tube at different site of digestive tract, and then comparing with the traditional methods, the point-of-care systems. RESULTS: Auscultatory method and aspirates from tube method have lower sensitivity(78.6%, 72.7%) and specificity (25.0%, 75.0%) ; bedside ultrasound(vessels signe) method sensitivity (100%), accuracy (100%) , positive predictive value(100%), negative predictive value(100%) and precision ratio are all higher than auscultatory method and aspirates from tube method, the difference was statistically significant(P<0.05). CONCLUSION: The bedside ultrasound vessels signe method has more advantages in confirming the location of the tubes at sensitivity , accuracy , specificity and positive predictive value than the traditional methods.

[Follistatin-like 1-engineered mesenchymal stem cells prevent myocardial ischemic reperfusion injury].

OBJECTIVE: To investigate the role of follistatin-like protein 1 (FSTL1) on bone marrow mesenchymal stem cells (BM-MSCs)-mediated cardioprotection during myocardial ischemia/reperfusion injury. METHODS: Rat bone marrow mesenchymal stem cells were isolated by whole bone marrow adherence method in vitro. A total of 60 Wistar rats were randomly divided into 4 groups: control group, ischemic /reperfusion injury (IRI) group, ischemia/reperfusion injury group treated with natural BM-MSCs (IRI+ MSC group), ischemia/reperfusion injury group treated with BM-MSCs which did not contain FSTL1 (IRI+ MSC FSTL1 siRNA group). Survival analysis was used to analyze survival time of rats, besides, expression of FSTL1 was detected by Western blotting. Myocardial pathological changes were detected by Hematoxylin and Eosin (HE) staining. Terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) and enzyme-linked immunosorbent assay (ELISA) were used to determine the associated biomarkers and apoptosis 7 days after operation. RESULTS: Compared with IRI group, rats in IRI+ MSC group had a higher survival rate and lived longer. Meanwhile, IRI+ MSC group had higher FSTL1 expression in blood and myocardial tissues than IRI group. Control group showed significantly lower apoptosis rate of myocardial cells[(1.4±0.1)% vs (29.8±4.5)%, P<0.05], less histological changes and infarction areas (0 vs 24.48±4.27, P<0.05) than IRI group. Compared with IRI group, IRI+ MSC group had an improvement of apoptosis rate[(4.2±0.3)% vs (29.8±4.5)%, P<0.05], less histological injury and infarction areas (15.12±3.82 vs 24.48±4.27, P<0.01). IRI+ MSC group had lower expression of LDH, MDA, CK and higher expression of SOD than IRI group (P<0.05). However, IRI+ MSC FSTL1 siRNA group showed weaker protection of myocardial cells than IRI+ MSC group after knockdown of FSTL1 (P<0.05). CONCLUSION: FSTL1, which was secreted by BM-MSCs, plays a protective role in myocardial IRI.

[The effect of Notch1 on myocardial ischemia reperfusion injury].

OBJECTIVE: To investigate the protective effects of Notch1 on myocardial ischemia reperfusion injury and explore underlying molecular mechanism. METHODS: H9c2 cells were exposed to hypoxia/reoxygenation (H/R), ischemic preconditioning (IPC) and ischemic postconditioning (IPost) treatment following infection with lentiviral vector-Notch1 intracellular domain (Lv-N1ICD) or Lv-N1ICD-shRNA, and divided into control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group, respectively. Apoptosis was detected by Annexin V/propidium iodide (PI), and reactive oxygen species (ROS) was detected by 2', 7'dichlorofluorescin-diacetate (DCFH-DA). The expression of p-glycogen synthase kinase-3ß (p-GSK-3ß)/GSK-3ß were detected by Western blot analysis. RESULTS: The apoptosis rate of cardiomyocytes in control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group was (5.34±1.70)%, (47.03±4.10)%, (33.89±12.25)%, (35.85±3.17)%, (51.12±8.22)%, (37.35±3.82)%, (47.90±3.08)%, respectively, showing significant differences in all group (F=18.47, P<0.05). ROS in control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group was 624.66±79.52, 1 221.87±63.66, 913.12±115.82, 935.85±201.62, 1 204.03±113.82, 967.15±106.11, 1 296.59±222.38, respectively, showing significant differences in all group (F=8.77, P<0.05). The ratio of p-GSK-3ß to GSK-3ß in control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group was 0.58±0.12, 0.62±0.20, 1.24±0.09, 1.16±0.12, 0.72±0.15, 1.16±0.12, 0.75±0.12, respectively, showing significant differences in all group (F=11.21, P<0.05). CONCLUSION: As an endogenous cardioprotective factor, Notch1 reduces myocardial ischemia reperfusion injury by promoting GSK-3ß phosphorylation, inhibiting cardiomyocyte apoptosis and reducing ROS formation.

Transthoracic closure of atrial septal defect and ventricular septal defect without cardiopulmonary bypass.

The minimally invasive surgical transthoracic occlusion of an atrial septal defect (ASD) or a ventricular septal defect (VSD) is an increasingly widespread alternative treatment for congenital heart disease. The aim of this study is to summarize our clinical experience with minimally invasive surgical transthoracic occlusion of ASD and VSD without cardiopulmonary bypass (CPB). Between April 2011 and October 2012, 27 patients with ASD and 95 patients with VSD (78 men and 44 women) were considered for minimally invasive surgical transthoracic occlusion without CPB. A small infrasternal incision (2.0-4.0 cm) was made under general anesthesia, under transesophageal echocardiography (TEE) guidance; the ASD and VSD were closed by using an appropriate occluder; and TEE was performed simultaneously to demonstrate the position of the device, any residual shunting, or encroachment on the atrioventricular valve, coronary sinus, or aortic valve. Successful transthoracic occlusion was performed in all 122 patients without complications. No complications such as third-degree atrioventricular block and residual shunting occurred after the procedures. The ventilation time was 2.2 ± 1.2 h, and the average length of hospital stay was 4.7 ± 1.7 days. All patients received aspirin at 3 mg·kg(-1)·day(-1) (maximum 100 mg/day) 24 h after the procedure. Minimally invasive surgical transthoracic occlusion without CPB is a new treatment that has many advantages such as causing little trauma, promoting quick recovery, having less complications, and avoiding radiation damage. However, the appropriate selection of patients is still key to improving the success rate of the operation.

Increased lymphocyte DNA strand breaks in rubber workers.

OBJECTIVE: To study the effect of occupational exposure to rubber processing, smoking, and alcohol drinking on lymphocyte DNA damage. SUBJECTS AND METHODS: Of 371 employees (197 men and 174 women) from a rubber factory in Guangzhou, 281 were rubber processing workers from five production sections and 90 were managerial workers. Information on occupational exposure, smoking, and drinking was collected by interviews. Blood samples were taken in the morning by venipuncture. DNA damages were measured by the Comet assay. Possible DNA-protein crosslinks were broken down by proteinase K. Tail moment, measured by Komet 4.0 image analysis software, was the measure of DNA damage. RESULTS: The rubber processing workers had larger tail moment than the managerial workers (Geometric mean, 95%CI) [1. 77microm (1.64-1.90) versus 1.52microm (1.36-1.71), P=0.04]. Both smoking [1.93microm (1.74-2.13) versus 1.59microm (1.47-1.71), P=0. 003] and alcohol drinking [2.21microm (1.87-2.62) versus 1.63microm (1.53-1.74), P<0.001] increased tail moment. Tail moment differed significantly among job categories (F=3.21, P=0.008), the largest was observed in mixers. In the non-smoking and non-drinking workers, rubber processing workers had larger tail moment than managerial workers after adjusting for age (P=0.033). General linear model analysis showed that after adjusting for each other, occupational exposure (P=0.027), smoking (P=0.012), and alcohol drinking (P=0. 013) was associated with larger tail moment, whereas age and gender had no effect. CONCLUSIONS: Occupational exposure to rubber processing, smoking, and alcohol drinking can cause DNA damage.